Can I run in a thunderstorm?
No. If you hear thunder you are likely within striking distance, and there is no safe place outside when thunderstorms are in the area. Get into a substantial building or an enclosed metal-topped vehicle with the windows up, and stay there until 30 minutes after the last clap of thunder.
Guidance from US National Weather Service / NOAA
Conditions
| Conditions | Risk | What to do |
|---|---|---|
| Storms forecast, none audible | Caution | Run a short loop close to shelter rather than an out-and-back that strands you. |
| Thunder audible, however distant | Do not run | Stop and get inside now. Distance counting does not make this safer. |
| Lightning visible | Do not run | Shelter immediately in a building or hard-topped vehicle. |
| Less than 30 minutes since the last thunder | Do not run | Stay inside. Most lightning deaths happen at the beginning and the end of storms. |
What to do
- Treat thunder as the trigger. Any thunder you can hear means lightning is close enough to reach you.
- Move to a substantial building with electricity or plumbing, or an enclosed metal-topped vehicle with the windows up. There is no safe place outside when thunderstorms are in the area.
- Stay in safe shelter until at least 30 minutes after the last sound of thunder. Do not wait for rain to start before sheltering, and do not leave because the rain has stopped.
Practical habits from us rather than instructions from US National Weather Service / NOAA. Useful, but not the same kind of claim as the bands above.
- Check the forecast before long runs in storm season, and plan a route that keeps you near shelter rather than out at the far end of a loop.
- If a storm is forecast, run earlier. Afternoon and evening are when convective storms usually build.
- You hear thunder. That is the signal — do not wait for rain, and do not wait for a closer one.
- Your hair stands on end or you feel a tingling sensation — a strike may be imminent.
- You are the tallest thing around, or near the tallest thing around.
- You are on open ground, on water, or on high exposed terrain.
Why
Lightning is the one weather risk in running where the correct response is absolute rather than graded. There is no version of a thunderstorm in which continuing a run is a reasonable trade.
Why the guidance changed
For years the standard advice was the 30/30 rule: count the seconds between flash and thunder, shelter if under thirty. NOAA no longer promotes it, and the reason is straightforward — if you can hear thunder at all, lightning is already within about ten miles, and strikes routinely occur outside the rain. Counting seconds gives a feeling of precision about a risk that does not offer any.
The current message is "When Thunder Roars, Go Indoors", and it is deliberately blunt because the failure mode of the old rule was people talking themselves into one more mile.
The two genuinely safe places
A substantial enclosed building with wiring and plumbing, or a hard-topped vehicle with the windows up. Both work because they conduct current around the occupants rather than through them.
What does not work: trees, open-sided shelters, bus stops, bridges, dugouts. The National Weather Service puts it without qualification — there is no safe place outside when thunderstorms are in the area. Anything that is not a substantial building or an enclosed metal-topped vehicle is a place to be leaving, not a place to wait.
The beginning and the end of storms
A high proportion of lightning casualties occur before the rain arrives or after it has stopped, when the sky looks survivable and people go back outside. That is what the 30-minute wait exists for, and it is the part of the guidance most often ignored.
Related questions
Is the 30/30 rule still the guidance?
Not as the primary rule. The older 30/30 guidance told you to count the seconds between flash and thunder and shelter if it was under thirty. Current NOAA and National Weather Service messaging is simpler and more conservative: when thunder roars, go indoors — any audible thunder means lightning is within range. The 30-minute wait after the last thunder does remain part of the guidance.
How far away is lightning if I can hear thunder?
Thunder is generally audible up to roughly ten miles, and lightning can strike well outside the rain area of a storm. That is precisely why the guidance stopped relying on estimating the distance.
Where is safe if I get caught out?
A substantial enclosed building, or a hard-topped vehicle with the windows closed. A shelter with open sides, a tree, a bus stop, or a dugout are not safe. If nothing is reachable, keep moving toward shelter and avoid open ground, water, high points and isolated tall objects.
Is it safe to run in heavy rain without thunder?
Rain itself is mostly a comfort and traction problem rather than a danger. The risks worth managing are reduced visibility to drivers, cold once you stop, and slippery surfaces.
Sources
- Lightning Safety — “When Thunder Roars, Go Indoors” — US National Weather Service
- Lightning Safety — outdoor safety one-pager — US National Weather Service